Store clerk critically injured after another David Hasselhoff sign theft

U.S. actor and singer David Hasselhoff poses on the red carpet before the MTV Europe Awards ceremony in Berlin November 5, 2009. REUTERS/Fabrizio Bensch (GERMANY ENTERTAINMENT)

David Hasselhoff drives his mini Cooper and reads Life and Style magazine as he is leaving the Ivy in Beverly Hills May 3, 2005 X17agency exclusive (x17)

USA ONLYDavid Hasselhoff, Britain's Got Talent judge, arriving at the Empire Theatre for second round of auditions in Liverpool on January 22, 2011. X17online.com *** Local Caption *** . BigPictures/X17online.com (X17online.com)

Connecticut police say a convenience store clerk has been critically injured trying to stop the theft of two signs featuring images of actor David Hasselhoff.

The signs featuring him advertising iced coffee. Officials say more than 500 of them have been stolen from stores in several states in recent months.

Authorities say a 36-year-old clerk at a Cumberland Farms in Shelton saw a man put the signs into an SUV shortly after 1 a.m. Tuesday. Police say the worker was struck and dragged by the SUV and landed on his head.

Police say the clerk is hospitalized in critical condition, and authorities are looking for the suspects. The employee's name hasn't been released.

On Aug.17, the actor tweeted a video of one of the signs attached to an airplane, flying above a crowd on a beach.

"Thanks to @cumberlandfarms and Jeff! You guys rock! What a cool banner," he wrote.

Hasselhoff is best known for his starring roles in the TV shows "Baywatch" and "Knight Rider."

The Associated Press contributed to this report.